abdominal aorta

The abdominal aorta (known in anatomical terminology as abdominal part of aorta) is the largest artery in the abdominal cavity. It is a continuation of the thoracic (descending) aorta and supplies oxygenated blood to most of the abdominal organs, the pelvis, and the lower limbs.

The abdominal aorta runs vertically along the midline of the abdomen, lying just in front of the lumbar vertebral column. It begins at the aortic hiatus of the diaphragm and ends by dividing into the two common iliac arteries at approximately the level of the fourth lumbar vertebra.

The abdominal aorta distributes oxygenated blood to the abdominal organs through major branches including the celiac trunk, superior and inferior mesenteric arteries, renal arteries, and gonadal arteries, as well as to the diaphragm, lumbar muscles, and pelvic structures.

The most clinically significant condition affecting the abdominal aorta is an abdominal aortic aneurysm (AAA), in which the vessel wall weakens and balloons outward, risking life-threatening rupture. Atherosclerosis and aortic dissection can also affect this structure.

While both are segments of the same aorta, the thoracic aorta supplies the chest organs and upper body structures, whereas the abdominal aorta supplies the abdominal viscera and lower extremities. The abdominal portion begins after the aorta passes through the diaphragm.